Pope Benedict XVI's views on homosexuality and the use of condoms, echoed by the incoming head of the English Catholic church, Archbishop Nichols, invite reflection on the problem of the evolution of religious ideas among the heirs of Judeo-Christian culture. For Jews the basic source of religious thinking is the Hebrew Bible and for Christians the Old and New Testaments. Scripture is read in both communities within their respective interpretative traditions. Yet despite the commonly professed subjection to scriptural guidance, one is puzzled by the diversity of understanding of the message of the Bible.

Take for instance the progressive Catholic attitude to the idea of creationism. In the view of the fundamentalists of every denomination the biblical stories of the Book of Genesis are literally true. Is genuine Christianity obliged to adopt this position? "No, it is not", we heard recently no less an authority than Cardinal Cormac Murphy O'Connor declare. Yet if he had given the same negative reply a century ago, he would have been obliged to face the growling Biblical Commission of the Vatican. Its decree of 30 June 1909, published in the official journal of the Roman church, forbad Catholics to question the historicity of the creation accounts in Genesis as they contained the "objective reality and historical truth of events which really happened". All one can conclude from the complete volte-face performed by a progressive Catholic that the development of ideas during the last hundred years has been considerably faster than that of the species investigated by Darwin.

Such a conflict of ecclesiastical opinions immediately raises the question of the role of the Bible in the thinking of the peoples of the book. Those who stick to a pre-Darwinian concept of the creation believe that the words of scripture must be taken as gospel truth wrapped in the infallible tradition of the religious authority. But grownup believers long for probing questions rather than for a constant dishing out of ready-made answers. Indeed, those who permit science and reason to influence their worldview dare utter the magic word, reinterpretation. A sensible move, think the moderates, but the summit of folly for Bible-bashers and slavish church devotees.

Another problem arises with the plurality of scriptural traditions, a common phenomenon already in the Hebrew Bible. For centuries after their conquest of the Holy Land around 1200 BC, the Jews offered sacrifices in temples located in the various cities of the land. But from the seventh century BC onwards Jerusalem became the only legitimate place for worship, and engendered fresh legislation which remained valid even after the destruction of the Temple in AD 70 and prevented the Jews from building a new place of sacrificial worship anywhere else.

In the Gospels, too, we find two separate rulings about divorce. That given in Mark and Luke, forbids divorce in all circumstances, but Matthew has an exception close: divorce is permissible on the ground of the wife's unchastity. Even that moral rigorist, St Paul, allows a Christian spouse to remarry if the pagan partner refuses peacefully to cohabit with him or her. So it was up to Christian religious authorities to make their choice. Some outlaw divorce, others permit it in some cases.

A third eventuality arises when changed social circumstances cause contemporary ideas to clash with scripture. The obvious examples are the ordination of women and homosexuality. Today's western society is inclined to sanction both. Yet the Bible provides no loopholes. There are no female apostles in the Gospels and St Paul positively silences women in the churches. (Traditionalism produces similar dictates in Judaism, too, making it inconceivable to have female rabbis in an orthodox synagogue.)

About homosexuality, while Jesus said nothing on the subject, no one could be more vituperative than Paul. Dare I quote him referring to "degrading passions", to women exchanging natural intercourse for "unnatural", and to men committing "shameless acts with men"? Paul once managed to survive stoning by enraged Diaspora Jews; would he dare face the gay liberation front?

To solve the dilemma created by the clash between modern mentality and millennia old holy writ one must ask what Moses, Jesus or Paul would think, say or do if they lived today. Would Moses still speak of Israel as the only chosen people of God? Would Jesus announce the coming of the kingdom and Paul the return of Christ during the lifetime of the current generation? What the present day religious mind needs is pragmatic common sense.

This thought reminds me of an anecdote I read not long ago. Some years after the appearance of On the Origin of Species, Darwin's great nephew, the future composer Ralph Vaughan Williams, overheard the adults discussing the book. He asked his mother what all that argument was about. This was her significant reply:

The Bible says that God made the world in six days. Great Uncle Charles thinks it took longer: but we need not worry about it, for it is equally wonderful either way.

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